Grid computing systems are conventionally known. In a grid computing system, plural computers connected through networks perform processes in parallel. A technique is present of implementing a grid computing system using a mobile communication system.
A distributed processing system is present that includes a base station and an on-vehicle terminal that can be connected to each other by radio communication. In the distributed processing system, the on-vehicle terminal acquires position information and a scheduled running route of the on-vehicle terminal, and the service area of the base station; and based on the acquired information, estimates whether the on-vehicle terminal is located within the service area of the base station. When the on-vehicle terminal estimates that the on-vehicle terminal is located within the service area of the base station, the on-vehicle terminal prepares for registration of the on-vehicle terminal into the distributed processing system. According to a movement direction notifying method, when the location of a communication terminal apparatus can not be identified, it is determined that the communication terminal apparatus is located outside a service area; the movement direction of the communication terminal apparatus after the communication terminal apparatus has moved outside the service area is estimated based on time information and position information of the communication terminal apparatus; and information concerning the movement direction of the communication terminal apparatus is reported to another communication terminal apparatus that requests connection to the communication terminal apparatus whose location is determined to be outside the service area (see, e.g., Japanese Laid-Open Patent Publication Nos. 2007-87273 and 2007-116330).
In the grid computing system, when the computers executing the parallel processing are each a mobile terminal such as an on-vehicle terminal or a mobile telephone, the base station communicating with the mobile terminal has to collect from the mobile terminal getting out of the service area of the base station, the process that is assigned to the mobile terminal. The base station has to assign the collected process to another mobile terminal located within the service area of the base station and cause the other mobile terminal to continue the execution of the process. However, many processes are necessary for assigning the process to the mobile terminal and collecting the process from the mobile terminal and therefore, the overhead becomes large. Consequently, a problem arises in that the efficiency of the distributed processing is degraded.